few days ago, during a crowded press conference, the reconstruction technique has been disclosed official NIST the collapse of WTC 7, which occurred several hours after the impact of two planes into the Twin Towers. (The original is found here While here is a video that recreates the dynamics Journal of the collapse). Below instead shows the reconstruction of the dynamics presented in the pages of The New York Times.
For the uninitiated the NIST (National Institute of Standards and Technology) is the U.S. institution that has been officially appointed by a U.S. law to investigate the causes of all failures occurred in the territory of buildings U.S.. For this reason you can imagine with what anxiety they had waited for years the results of investigations into what is almost immediately appeared to observers as a collapse, if possible, technically more "problematic" than that offered by the same Twin Towers.
But we now see specifically what are some of the FAQ on the report published, which were presented on the website of NIST (the translation is taken from this page ):
What Was the WTC 7?
The World Trade Center Building 7 (WTC 7) the original building was a 47-story Office Building, located directly north of the main World Trade Center (WTC). Completed in 1987, was built over an existing Con Edison electrical substation on land owned by the Port Authority of New York and New Jersey.
When WTC7 collapsed?
September 11, 2001, WTC 7 endured fires for almost seven hours since the collapse of the WTC North Tower (WTC 1) at 10:28:22, until 17:20:52, when WTC 7 collapsed.
What caused the fires in WTC 7?
The debris of the collapse of WTC 1, which stood at about 110 m away to the south, sparked fires on at least 10 floors of the building at its south and west facades. However, only some of the fires on lower floors from the 7th to the 9th and 11th to 13th floor, burned out of control. These fires on the lower floors, which spread and grew because the water supply to automatic sprinkler system for these floors was out of use were similar to the fires of other tall buildings. The primary and secondary water supply for sprinkler systems to the lower floors depended on public water systems, whose lines had been damaged by the collapse of WTC 1 and WTC 2. These uncontrolled fire spread to lower floors due to the north-east of WTC 7, where he began the collapse of the building.
How fires caused the collapse of WTC 7?
The heat of uncontrolled fires caused thermal expansion of beams and slabs of steel beams, leading to a chain of events that caused the collapse of a structural column fundamental. The structural failure in this column then triggered a progressive collapse, caused by fire, the whole building.
According to the report of the probable collapse sequence, the heat coming from the uncontrolled fires caused thermal expansion of steel beams on the lower floors of the east side of WTC 7, damaging the structure of the floors on different levels.
At one point, a beam on the 13th floor lost its essential connection with a column, the column 79, which supported the long span of the floors on the east side of the building. The beam out of the office and other local damage caused by fire caused the collapse the 13th floor, starting a chain of progressive failure of the floors down to the 5th floor. Many of these plans had already been at least partially weakened by the fires in the vicinity of the column 79. This collapse of floors left the column 79 without sufficient support in the east-west extension of nine floors.
The column 79, with no support at this point he bent and triggered a progression upwards of subsidence of the floors, reaching the east lining roof of the building. What followed in rapid succession, was a series of structural failures. The first failure occurred up to the roof and interested all three columns inland on the eastern side of the building (columns 79, 80, 81). Then, with a progression from east to west across WTC 7, gave all the columns in the core of the building (from 58 to 78). Finally, the entire façade collapsed.
The debris from the collapse of WTC 7 WTC 1 damaged the structure so as to contribute to its collapse?
(...) A separate analysis showed that even without the structural damage caused by the impact of the debris, the fires in WTC 7 would collapse similar to those that occurred on 11 September 2001. (...)
It 'obvious that such an explanation on the collapse of the skyscraper, for As you may be, like me, very little experience on building structures and analysis of the collapses, it leaves much astonished, especially when you notice that the same NIST, in another FAQ is expressed in these terms:
Why WTC7 collapsed, while history does not record any buildings collapsed due to fire only?
The collapse of WTC 7 is the first known case of a tall building collapsed mainly due to uncontrolled fires. The fires in WTC 7 were similar to those that occurred in several tall buildings where the fire extinguishers and automatic rain did not work or were not present. These other buildings, including the One Meridian Plaza di Philadelphia, un grattacielo di 38 piani che bruciò per 18 ore nel 1991, non crollarono per via delle differenze di progettazione del sistema strutturale. (...)
In pratica dopo anni e anni di studi che immaginiamo essere stati accurati e approfonditi come mai prima d’ora (ricordiamo che la pubblicazione della versione ufficiale del NIST relativa al crollo delle due Torri è avvenuta in tempi relativamente molto più brevi), i ricercatori ci dicono che il WTC7, grattacielo di 47 piani, è crollato ESCLUSIVAMENTE a causa degli incendi e soprattutto, voglio sottolinearlo bene, che questo è avvenuto PER LA PRIMA VOLTA NELLA STORIA.
Ora, chi legge questo blog da un po’ sa che in materia di September 11 we have already treated some curiosity and expressed some doubts, but we have never expressed a priori in favor of this or that thesis, knowing that in a matter so strictly connected to the very complex factors, the review of human road can hardly reach to touch the truth or at least a sense.
However, in this case, it seems only right to say that what is stated in (quite late ...) official version is really very difficult to swallow for a number of reasons that I would argue.
always, in all publications and websites committed to refute and counter the arguments carried out by those who express doubts about the collapse of 11 September, it was said with plenty of arguments, apparently shared, it was misleading and "mischievous" said that WTC 7 could have collapsed in a way, so to speak, "natural" does not having been directly hit by any plane, and this because, according to the "supporters of the anti-conspiracy" in the same building had suffered irreparable structural damage from the rubble of the towers collapsed on it, were originally at the edge together with the fire of its failure (see for example this page of "September 11th", which are very rich in images and also effective to frame the scene of events).
Today, wanting to mention Guareschi "countermand, comrades." The technical official version tells us explicitly that the debris did not create any direct decisive, but the collapse was exclusively due to fires ignited, as demonstrated, among others, by following the NIST FAQ:
The WTC7 would collapse also if there had been no structural damage caused by the collapse of the WTC towers?
Yes, even without structural damage, WTC 7 would collapse because of fires triggered by debris. (...)
So the two, one: either the so-called "debunkers" are have proved in this case a lot rougher and incompetence of much-despised "conspiracy theorists" or is the official version of NIST to be very hard to believe in coming after seven years of research to disprove all the experts, technicians and "lawyers" previously been involved the question ...
A second aspect is really not very convincing to accept that the duty of WTC7 after the collapse, not even a stump left, an inside wall or a piece of standing, which we might legitimately have expected, taking into account the fact that the cases were detected only in the fires and the resulting (?) collapse of a single column building. Why then would have to demolish the skyscraper in full? Whilst it may be that you have the Rate "progressive collapse" described by NIST, why should it be full? This is not explained, at least not in a clearly understandable and shareable.
Consequently, the official version released today leads naturally to the question: if the perfect and complete collapse of a skyscraper of 47 floors as WTC 7 was solely due to failure of a single column, as stated by NIST in practice, for which reason the demolition of buildings and artifacts usually by explosive undertake dozens of offices targeted to sever the various points of support? Possible that this very building, which happened in the middle of the most amazing and spectacular (and discussed) attack of all time, has proven to be a pure case of the most unique (and fragile ...) examples of architecture may we know ?
In accordance with the theory known as "Occam's razor ," so popular and often cited by the so-called "debunkers", which says that for every phenomenon, the simplest solution is always preferable, I find it very hard to believe.
For the same reason, while appreciating the very concept of "suspension of disbelief" when I read a novel, a comic or watch a good movie, I believe in good faith that they can not get to the point where I am asked to accept that in a single day, as extraordinary as that of 11 September, on the whole of the World Trade Center are verified in less than three hours full of skyscrapers collapsed, burned to the ground from the tip of the antennas to the foundation, all held by different parties and with a wealth of arguments very little credibility or not yet convincingly explained, and among them one in particular ( WTC 7 just) about the same as the official version after seven years of research tells me literally be "the first known case of a tall building collapsed mainly a causa di incendi incontrollati ”.
Infine, anche a proposito del colpevole individuato dal NIST, ossia proprio gli incendi incontrollati, da più parti si è fatto rilevare in questi anni che la loro estensione e gravità non appariva comunque tale da giustificare la rilevanza del danno asserito (vedi ad esempio questa pagina , con tanto di foto e video).
Detto ciò, vorrei anticipare subito una domanda che potrebbe essermi rivolta, a questo punto, da un sostenitore della versione ufficiale del NIST e che potrebbe suonare così: “ ma allora, se non ti sembra credibile questa versione, perché non ci spieghi tu, come è andata..? ”
My answer is as simple and straightforward: not even think about it!
I'm not an expert in building structures and dynamics of the collapse of the same and I do an act of intellectual honesty, as always when I dealt with the September 11 attacks, the profession of ignorance and refuse to marry any preconceived thesis that I have not been demonstrated in terms understandable and acceptable. I think even in principle that events on a scale so vast, it is usually almost impossible to reach the ascertainment of truth in an integral and then I'm afraid we'll never know what exactly happened that morning in September 2001 and which have been le esatte circostanze che vi abbiano condotto.
Tuttavia, sempre per la stessa onestà intellettuale, ritengo che sia assolutamente legittimo, se non addirittura doveroso, manifestare liberamente alcuni dei dubbi e delle riserve che una simile “incredibile” versione ufficiale, giunta a tanta distanza temporale dagli eventi e risoltasi in definitiva in una candida affermazione della inedita unicità del più "strano" dei crolli avvenuti al World Trade Center, ha fatto nascere in me.
Mi riservo quindi in conclusione di tornare presto sull’argomento con altre riflessioni e nel frattempo vi invito ad esprimere qui le vostre opinioni e i vostri commenti, di qualunque tenore esse siano.
0 comments:
Post a Comment